Dyestuff composition



Patented Apr. 15, 1941 UNITED STATES DYESTUFF COMPOSITION Norman S. Cassel, Ridgewood, N. J., assignor to Interchemical Co p ration, New Yflrk, Y a

corporation of Ohio.

No Drawing. Application January 10, 1940,

Serial No. 313,202

Claims.

The invention relates to the art of textile decorating, and is directed particularly to new compositions intended for textile decorating, comprising dispersions of dyestufi ingredients so designed as to remain stable in'storage for extended periods of time.

The conventional method of textile printing involves the application to a textile fabric of a dyestuff, or an ingredient of a dyestuif, in water solution, by means of an intaglio cylinder. In order to get the dyestuif solution thick enough to remain in the cells of the printing cylinders, and to remain in place when applied to the fabric, water-soluble thickening agents such as British gum, starch and the like are used. More recently, wetting agents have been added to ,the pastes to improve their printing properties. After printing, the dyes are set by various means so that they become water-insoluble, and the fabric is washed to remove the water-soluble thickeners.

Certain difficulties are encountered with. these conventional dyestufi pastes. Since the fabrics printed are rather water-absorbent, prints made with water solutions, even when made viscous with the water soluble thickeners, tend to spread out slightly from the point of application, a phenomenon known as flushing. As a result, the lines in the engraving may become somewhat blurred, and very fine lines close together may be entirely lost. When the viscosities of the pastes are adjusted so that no flushing occurs, the pastes become too thick to separate cleanly from the engravings. A compromise must always be made, so that effective separation occurs without substantial flushing; and the cylinders must be so prepared as to print most easily. Fine photogravure engravings have, as a consequence,

never been used with conventional textile printlng .pastes, because their faithful reproduction of detail would not register on the fabric. Furthermore, the engravings used must be rather deep in order to get effective printing, and considerably more paste is used than is really necessary to produce most designs.

Another disadvantage of conventional dyestuff pastes is that a substantial quantity of dyestufi may be washed out with the thickeners. This is due partially to mechanical suspension of converted dyestuff in the film of thickener, partially to incomplete conversion of the dyestuif, to the r insoluble form, due to the trapping of the soluble dyestuff inside of the thickener film, and, in some cases, partially to actual dyeing of the thickener. This may represent a serious loss of dyestuif.

In my copending application, Serial Number 215,585, filed June 24, 1938, of which this is a continuation in part, I have disclosed a means whereby these disadvantages may be overcome, and successful dyestuif printing can be done with photogravure and other relatively shallow en- 1 mg in the discontinuous phase.

emulsion, of optimum consistency for printing, is

tail of the photogravure cylinders, and the use of a. minimum of dyestufi. As therein disclosed, this means comprises the preparation of dyestufif printing pastes by the emulsification of an aqueous solution of a dyestufl or a dyestuif component capable of producing permanent dyeings on the fabrics with a water immiscible bodying composition (preferably a solution of a film-forming substance in a solvent), the dyestuff solution be- The resultant applied to a fabric, as with a conventional intaglio cylinder; the dyestufi is fixed on the fab- .ric, and the fabric is then dried, with or without washing, depending on the dyestulf employed.

As the emulsion is applied to the cloth and the emulsion breaks, the dyestufi solution penetrates into the yarns of the fabric. Since the water phase and the bodying agent are mutually repellent, the non-aqueous phase prevents undue are as difficult to print as cotton flannels.

While these emulsion pastes are unusually effective printing media} a serious difficulty with their use rises from the fact that many dyestuif ingredients, particularly of the dlazo type, are

unstable in the presence of water, so that color strength is lost on storage of the pastes.. This necessitates making up small batches of these colors at the print plant, as they are needed, with the inconvenience of measuring out small quantitles of these dyestuif ingredients, and the danger of contamination of other print colors.

I have discovered that dyestuffs and ingredients thereof which are unstable in the presence of water may be dispersed in emulslfiable nonaqueous liquids, that the resultant dispersions can be stored just as long as the dry powder without deterioration, provided the liquid has no appreciable solvent action on the dyestufi, and that the non-aqueous liquids, on the addition of water or aqueous alkalies rapidly and completely yield up the dyestuif to the water. I am thus able to prepare a readily emulsifiable base in which the colors are stable, and which can be rapidly stirred up at the print plant with water and other desired ingredients, to obtain a finished printing paste without the necessity for careful weighing of small amounts of dye powder, with the resultant errors in strength of color, and with the resultant danger of. contamination of other printing pastes.

The unstable dyestufl components are l y of the class known as naphthol fast color salts, and comprise a large group of diazo compounds which can be coupled with beta-oxy-naphthoic acid and its derivatives. In'general, these dyegravings, with the retention of the complete destuff components are printed onto a fabric conments which reconstitute the two units in such form that they can couple.

The emulsifiable liquid should preferably be a solution of a film-forming substance in a volatile organic solvent, since these materials are desirable in the finished printing paste, and since they can be made sufficiently heavy in body to maintain the dyestulf dispersed through the mass.

The dissolved substance should be sufficiently film-forming to be capable of forming films about the water globules, and thus ensure proper emulsification. I

Provided the solution produces satisfactory water-in-oil emulsions, substantially any solvent and any film-forming substance may be used, depending on the dyestuff employed; but care must be taken that neither has any appreciable solvent action on the particular dyestuff being dispersed The cellulose esters and ethers may be generally employed, since as a class they have solvent action on very few dyestuffs; ethyl cellulose is a preferred material because it appears to be inert to all of the *water unstable dyestuffs, and because it yields good emulsions even when usedin very small amounts. Milled rubber, and similar products (rubber derivative resins, chloroprene polymers, iso butylene polymers, and similar rubbery linear aliphatic polymers) and the resins derived from the polymerization of olefinic hydrocarbons are also excellent with most dyestuffs. The resins derived from aromatic hydrocarbons (cumarone-indene type) and the oxygen-containing synthetic resins (alkyd, phenolic, urea, etc.) should be used with caution,

. as they tend to have a solvent action on some dyestufis. Bodied fatty oils are also satisfactory in general and most of the natural resins mayalso be used. Of the common solvents, the aliphatichydrocarbons and hydrogenated petroleum hydrocarbons likewise have no effect on the dyestuffs. The lower aromatic hydrocarbons are also satisfactory; but cuts above xylol often have a' solvent action, and should be avoided. The

'terpenes, particularly when contaminated with This dispersion can be made into an acceptable printing paste by adding- Parts Pine oil 3 Solvesso #3 (hydrogenated petroleum hydrocarbons. Boiling range 175210 C.)

. Above dispersion 14 and then emulisfyingin Water to yield a water-in-lacquer emulsion of excellent printing properties, which can be printed on a prepared ground (for example, one impregnated with beta-oxynaphthoic acid anilide) to yield an excellent print.

Example 2 Parts FastBlue Salt B (Schultz 490) 46 is dispersed in a colloid mill in a mixture Alkyd resin solution 46 Xylol a The alkyd resin solution is made by reacting 148 parts phthalic anhydride, 110 parts glycerol,

and 125 parts castor oil fatty acids at 230 C., in

the presence of carbon dioxide until the acid number is about 8, and then reducing to 50% non-volatile with a mixture of 30 parts pine oil and 70 parts Solvesso #2 (hydrogenated petroleum naphthaboiling range 135177 C.) This dispersion, like the last, is stable on storage.

is emulsified into the lacquer. A slight amount of acetic acid in the water phase improves the color value of this and many Example 1 Parts Red salt B (Schultz 31 is dispersed in a three-roll mill in a solution of 250 centipoise ethyl cellulose 5 in Xylol 64 This dispersion is stable on storage; the salt in water loses color strength rapidly, particularl'y-if not kept cool.

similar products.

Example 3 A duplication of Example 2, with Red Salt B (Schultz No. 155) proved unstable, apparently due to the solvent action of the alkyd resin on the salt. It should be'noted that this salt is stable in ethyl cellulose.

Example 4 -Parts Rapidogen Brown (General Dyestufi Cor r U. 8. Patent No. 1,822,561) 20 was dispersed on a three-roll mill in l 500 centipoise standard ethoxyethyl cellulose dissolved in Solvesso #3 -l and Pine oil 7 This is stable on storage.

This dispersion can. be made into an excellent printing paste by adding- Parts Above dispersion 21.6

Solvesso #3 14.7

Example P Rapidogen Green 13 (General Dyestui! Corp.

Other variations can be made without departin: from the scope of my invention, which is deiined in the claims.

U. 8. Patent No. 1,882,560) 30 is dispersed on a three-roll mill into 500 centipoise standard ethoxy ethyl cellulose 4 dissolved in Solvesso #3 59 and White pine oi 7 A printing paste can be made as in Example 4, from v Parts Above dispersion 14.3 Solvesso 22.0 Water 61.4

' mixed with v v Caustic soda solution 2.3

Example 6 Parts Fast Blue Salt B -(Schultz 490)-.

' is dispersed in Heavy kettle bodied linseed oil 30 Solvesso #2 (hydrogenated petroleum hydrocarbonboilingrange -177 C.) 10

A printing paste can be made with Parts Above dispersiom. '7 Solvesso 12 Water 81 Similar results are obtained with blown oils of various sorts.

' Example 7 f Parts The dyestufi of Example 5 12 is dispersed in a solution or 15' milled crepe rubber g 23 Solvesso #2 62 This dispersion makes an excellent printing paste with Parts Above dispersion 30 Solvesso 39 40' Be. NaOH solution 1.5 Water 29.,5

This application is a continuation in part of my application Serial Number 284,210, iiled July 13, 1939.

I claim:

1. A composition adapted to be emulsified comprising a dispersion of a material of the group consisting of dyestuiis and dyestufl components soluble in water, and dyestuffs and dyestuil! components soluble in dilute aqueous alkali, in a water-immiscible organic liquid having no appreciable solvent action on the dyestufi component, said liquid comprising a volatile waterimmiscible orgamc solvent having dissolved therein sufllcient oi. a water-insoluble film-forming substance to make the liquid capable of emulsifying water therein.

2. The composition of claim 1, in which the dyestuil is a water soluble diazo compound of the class capable of forming a dyestuil' on coupling with a compound of the class consisting of beta.- oxy-naphthoic acid and its derivatives.

3. The composition of claim 1, in which the dyestufl comprises an aqueous alkali soluble mix ture 01' a diazo compound and a coupling component stabilized against reaction in aqueous alkaline. solution.

4. A composition adapted to be emulsified comprising a dispersion 01! a material oi the group consisting of diazo dyestufls and diazo dyestui! components which areunstable on storage in aqueous solution, in a water-immiscible organic liquid in which the dyestufl is stable, said liquid comprising a volatile water-immiscible organic solvent containing suiiicient of a water-insoluble film-forming substance to make the liquid capable of emulsifying water therein.

5. The method of making a textile printing paste which contains a material of the group consisting of diazo dyestuils and diazo dyestuii components which are unstable on storage in aqueous solution, which comprises distributing the diazo dyestuir component through a water-immiscible organic liquid in which the diam dyestui! component is stable, said liquid comprising a waterimmiscible organic solvent containing suiilcient or a water-insoluble film-forming substance to make the liquid capableot emulsifying water therein, and emulsifying an aqueous solvent for the diazo dyestufl component into the dispersion before use to produce a paste of printable consistency.

NORMAN S. CASSEL. 

